Reaping orphaned children should be the duty of PID 1.
There is no objective basis for such a claim, this not actually being a
minimal requirement of process #1. Welcome to the future. Your service
manager does not have to be process #1. Your interactive logins are
ordinary services controlled by your service manager. Orphaned child
processes are reparented to your service manager or to some other
process that is even closer to them.